Whatever it was happened at 35,000ft so even if it stayed intact all the way down it would have smashed to pieces when it hit the water. If the pilots had time to try to land they would have sent out plenty of radio calls. It must have been very sudden if it just vanished, either an explosion or catastrophic structural failure.

The security people are also questioning how two men with Asian faces got through passport control with stolen Italian and Austrian names/passports and none of the officials thought to double check. Interpol puts stolen passport details out there but in many places the authorities can't be arsed to check. I predict that the fingerprint ID technology currently in use in some countries will now be expanded so you can't cross any border without a passport AND a fingerprint.

Edit: The men travelling on stolen passports were of "African appearance", not Asian. News reports here dance around these potentially significant facts due to our Media's terror of upsetting someone. It should still have been a red flag to passport control.

Edit #2: My dad (ex pilot) told me it takes around 4 minutes for a plane to fall from 35,000ft which is plenty of time (shudder) for pilots/pax to radio or phone someone somewhere or turn on various distress/location devices on the way down unless they were all suddenly incapacitated/killed at the same time.

But the complete lack of wreckage or debris is very odd. They know roughly where it should be if the last radar contact was accurate and even if heavy things like engines sank to the seabed, some luggage, seat cushions, etc would be floating by now. Even experienced air crash investigators are baffled. Maybe the hijacking/coverup theories are credible although whoever did that must have known exactly how to disable the radios and radar and prevent pax using their phones so it's not really plausible I'd have thought. I even heard one theory that the plane was hit and destroyed by a meteorite. Not impossible and it would explain the instant loss of communication.

But the complete lack of wreckage or debris is very odd. They know roughly where it should be if the last radar contact was accurate and even if heavy things like engines sank to the seabed, some luggage, seat cushions, etc would be floating by now. Even experienced air crash investigators are baffled. Maybe the hijacking/coverup theories are credible although whoever did that must have known exactly how to disable the radios and radar and prevent pax using their phones so it's not really plausible I'd have thought.

The oddest part is, even if the hijackers disabled the transponder, the plane would still show up as a "blip" on the radar screen. I'm not sure how low the radar coverage goes around that area, so maybe it's possible they flew the plane below radar coverage for a while before it met its fate. I don't know; I'm completely baffled.

Yeah, they can get "lost" because you can only track by radar over land. Starting to wonder if some catastrophic event happened - like a sudden decompression that incapacitated everybody - and maybe destroyed other systems on the plane. It had 7-1/2 hours of fuel on board, so theoretically, it could have gone that long and ended up in a jungle or on the side of a mountain where nobody's thought to look. Sounds like the search area is being expanded.

Over land, air traffic controllers can use two types of radar, primary, which detects objects by bouncing back a radio signal, and secondary , where the plane sends back an automatic response, identifying itself. Air traffic consultant Doug Maclean, of DKM Aviation, says: "Secondary surveillance radar sends out a coded question, the interrogation message will be received and sent back; that requires a degree of co-operation between plane and the ground. In the likes of the 9/11 incident, the aircraft would have received messages but hijackers had switched off the reply."But over longer distances where radar coverage is limited – ie usually when planes are flying across oceans – they use another system, Automatic Dependent Surveillance. Here the aircraft transmits its own signal and gives its position via satellites. Maclean says: "Once you go outside primary radar coverage, which would normally be about 100 miles offshore maximum, you are relying on the plane to be transponding."So when flight MH370 disappeared from plane tracking websites, it could mean the signals from the plane's transponder were stopped deliberately (by pilots or others), or there was a complete electrical failure, or the plane disintegrated. Where the Malaysian plane was flying, the signals are picked up by sites only once a minute and only at a plane's cruising height above 29,000 feet. So a dramatic loss of altitude could conceivably also see a plane drop off their radar but potentially continue to travel for some distance.

But, if some of the phones are still riniging - can't they locate the phones?

Originally Posted by A*O

Edit: The men travelling on stolen passports were of "African appearance", not Asian. News reports here dance around these potentially significant facts due to our Media's terror of upsetting someone. It should still have been a red flag to passport control.

Yesterday they told us that they looked like Mario Balotelli:

And today they show us those pictures:

But looking at the last pictures, I do understand why, even if they really checked the passport/name with the faces, that they didn't assume that they were stolen.

Earlier today Malaysian media reported that the plane was spotted flying at lower altitude some distance away from its intended flight path."The last time the flight was detected close to Pulau Perak, in the Malacca Strait, at 2.40 a.m. by the control tower before the signal was lost," air force chief Rodzali Daud told the Berita Harian newspaper.If correct that would suggest the plane flew for an hour and 10 minutes AFTER the plane vanished from control screens.

If the Malaysian military accounts prove correct they would appear to rule out catastrophic mechanical failure, as it would indicate the plane flew for a further 350 miles after disappearing from air traffic control screens.

That said all theories are still being checked and nothing is being ruled out at this stage.

While secondary radar - used by air traffic control - cannot locate an aircraft with a transponder turned off, the military use primary radar which could still track the plane.

What does that mean then, in terms of theories? Someone took over the plane? The pilot went nuts?

I would think that if the pilot went nuts, the other pilot would issue a mayday. Unless he was locked out of the cabin or something.

I seem to remember that the Egyptian copilot who purposely crashed an airliner a few years ago took the plane into a nose dive while the main pilot was on break. The flight recorder captured the copilot praying and then the main pilot coming in and saying, "What are you doing???" Then, trying unsuccessfully to pull the plane out of its dive. But nobody would have known about that if they hadn't found the flight recorder, I think. I don't think that dialog had been broadcast back to any control tower.

In this case, if they were veering several hundred miles off course, because of one of the pilots, it would seem that the other pilot would issue some distress signal. However, if terrorists had commandeered the plane, they could maybe have prevented the pilots from sending the signal.

But what terrorist group would be motivated to go after this flight? It was from Malaysia to China. Uighur separatists? Jemah Islaamiyah?